Enhanced Water Stability in Zn‐Doped Zeolitic Imidazolate Framework‐67 (ZIF‐67) for CO ₂ Capture Applications

In this work, the water stability of zeolitic imidazolate framework‐67 (ZIF‐67) is successfully enhanced by Zn‐doping during the crystallization process. Both elemental mapping analysis and X‐ray diffraction (XRD) results reveal that Zn element is doped in the ZIF‐67’s crystals. The thermal stability, surface area and CO 2 capacity are not significantly affected by Zn‐doping as evidenced by thermogravimetric analysis (TGA) and gas sorption. When exposed to liquid water, the doped ZIF‐67 s show better stability in terms of crystal structure, morphology, surface area and CO 2 uptake capacity. However, the undoped ZIF‐67 crystals collapse and nearly lose their porosity as well as CO 2 uptake capacity after the same exposure. This study provides a new approach to enhance the water stability of ZIF‐67.